<p dir="ltr"><br>
> One of the things that surprised me, when I removed the keyboard,<br>
> is that contacts on the end of the ribbon cable are *black* rather<br>
> than being either silver or gold in color as I was expecting.<br>
> Looking at it through a loupe, it looks like there's actually<br>
> a thin sheet of carbon or similar-looking material installed<br>
> as a layer over the contacts. Made me hesitate before trying<br>
> the alcohol swab; actually, it makes me wonder whether those<br>
> contacts are really cleanable at all.<br>
><br>
I'd swab them with alcohol. I've seen that a couple times, and each time it turned out it was corrosion. Not to say it couldn't be a factory coating, but if it looks like a gross old nickel, it's probably oxidized.</p>